According to the 'Alejandro' hitmaker's former manager Bob Leone, the eccentric star used to have trouble going on stage when she was a teenager and needed her mother for support.
He said: "She was painfully shy - very different from who she is now.
"She came to the open mic nights with her mother twice before she built up the courage to go onstage."
Bob also claims Gaga - real name Stefani Germanotta - transformed before him while he managed her for six months in 2006.
He said: "She was prodigy-like. She was clearly a very good songwriter and keyboard player.
"It was a very important six months because going into it, she was Stefani, and she was still writing pop music. By the end of that six month period, she was officially Lady Gaga."
She also developed her self-confidence when she became Gaga, eventually wowing crowds with her performances and always revealing her passion to "dominate" the music world.
He told People.com: "She blew everyone away. Nobody talked about anything after that show but Lady Gaga. She bantered with the audience and was very funny.
"Whenever someone asked her, 'What is your goal?' she would always give the same two-word answer, 'World domination.' "